Furnace-pipe



(No Model.)

H. McMILLIN. FURNACE PIPE.

No. 525,467. Patented Sept. 4, 1894.

. %2%%W V W Tu: mums mm :0. moraurnq, wanmm'ou. n. c.

UNITED STATES PATENT OFFICE.

HARRY MOlWIILLIN, OF ALLEGHENY, PENNSYLVANIA.

FURNACE-PIPE;

SPECIFICATION forming part of Letters Patent No. 525,467, datedSeptember 4, 1894.

Application filed December 15, 1893. Serial No. 493,784. (No model.)

To all whom it may concern:

Be it known that I, HARRY McMILLrN, a citizen of the United States,residing at Allegheny, in the county of Allegheny and State ofPennsylvania, have invented certain new and useful Improvements inFurnace-Pipes; and I do hereby declare the following to be a full,clear, and exact description of the invention, such as will enableothers skilled in the art to which it pertains to make and use the same,reference being had to the accompanying drawings, which form a part ofthis specification, in which Figure 1 indicates a perspective of myimproved hot air flue, broken away at one of the joints and bottom, toshow manner of connecting sections, and the cold air space between thewalls. Fig. 2 is an enlarged perspective of one of the sections. Fig. 3is an enlarged vertical section of portion of two sections, showingjoint between same.

My invention relates to flues located in the walls of buildings toconvey hot air from a furnace, to the various rooms of the same, andconsists of the novel construction and arrangement of parts hereinafterspecifically described, reference being had to the accompanyingdrawings, forming part hereof, in which like letters indicate like partswherever they occur.

Referring to said drawings A is an hot air flue adapted to be located inthe walls of a building for the purpose of conveying hot air from afurnace, to the various rooms in the same. Said fine is formed of aseries of sections a-a preferably of tin, the lower end of the innerwall b being beveled outwardly and overlapped upon the lower edge of theouter wall I)" the upper end of which is inclined inwardly, the upperend of the inner wall be-. ing overlapped upon the same as shown inFigs. 2 and 3, the beveled surfaces being provided with perforations,whereby a continuous cold air space is formed between the walls of saidflue, as shown in Fig. 1. Said flue is provided with a perforated coverc to enable the air (usually taken from the cellar, and consequently ismore or less impure) circulating between the walls of said flue, toprevent the same entering the room through the register, and is enabledto escape through the walls of the building.

One of the many advantages of my improvement; is the simplicity of itsconstruction, dispensing with the use of machinery, and consequentlyreduction in cost of the same.

Having described my invention, what I claim, and desire 'to secure byLetters Patent, is-

A hot air pipe for furnaces consisting of a number of sections, thelower end of the inner wall of each of said sections being turnedoutwardly at an angle of forty-five degrees to the lower edge of theouter wall and overlapped on said outer wall and provided withperforations, the upper end of the outer wall being turned inwardly onan angle corresponding with that of the lower end of the inner wall, andprovided with corresponding perforations, the inwardly inclined top ofone section being adapted to fit into the outwardly inclined bottom ofthe next succeeding section, and to be soldered thereon, and acontinuous cold air space formed between the walls of said pipesubstantially as described.

In testimony that I claim the foregoing I hereunto affix my signaturethis 13th day of December, A. D. 1893.

HARRY MGMILLIN. [L. 8.]

In presence of- J AS. J. MCAFEE, O. A. WILLIAMS.

